John Challis says that when he learned of Roger Lloyd-Pack's passing, he felt guilty.
The 71-year-old actor starred alongside the comedy legend for over two decades in 'Only Fools and Horses', and although he tried to contact his close friend the day before he lost his battle with pancreatic cancer last month, he still feels guilty.
He said: "I was sitting at my computer and I saw it on the internet ... I just put my head in my hands, I couldn't believe it. It was a terrible shock.
"You get afflicted by a sort of guilt. I felt guilty, that I should have done more, I should have known more - not that you can change anything."
John - who played second-hand car dealer Boycie in the long running sitcom - also revealed that he was disappointed he wasn't able to say goodbye to his pal, who was known for his role as dopey road-sweeper Trigger.
He told the Daily Mirror newspaper: "I wanted to say goodbye. But I understand why he didn't want it out there. He didn't want anyone to know he was ill."
Although he's sad to be losing more friends as he gets older, John's glad he still has memories with Roger and their fellow stars Sir David Jason and Nicholas Lyndhurst to look back on when he's feeling down.
He added: "In times like this I do think of 'Only Fools' and it makes me smile again. Although there is always that worry because you look back and see yourself 30 years ago. You say, 'Where has all our hair gone? Where is all our energy?' "
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